Hook rule and compass



July Z0, 1937. .1. KNoBLAucH A HOOK RULE AND COMPASS Filed Nov. 9, 1956Patented July 20, 1937 UNITED srgrss keine g resisto 'rforrice 4 laims.

This invention relates to precision instruments such as are used byarchitectsand machinists and more particularly relates to a combinationhook rule and compass.

An object of my invention is to enable the ordinary steel rule to beused as a hook rule and compass.

A rfurther object of my invention is topr'ovide a device of thecharacter described consisting of few and simple parts, relativelyinexpensive to make, efficient and positive in operation and embodyingfeatures of precision, accuracy and stability.

A further object is to provide a device of the character described,comprising a rule provided with a longitudinal groove, a rod positioned`in said groove, a channelled bracket adapted to hold a member,preferably a pin, against an end edge of the rule, said bracket beingremovably secured to the rod, and means engaging the other endy edge ofthe ruleand in engagement with the rod for holding said bracket and itsmember positively against the end edge of the rule.

A further objectof my invention is to provide a device of the characterdescribed comprising a rule, a slide longitudinally movable thereon,said slide having a tongue adapted to have frictional sliding engagementwith the rule, a stud depending from the slide, and a clamp engaging thestud to removably secure a line marking member thereto.

A further object of my invention is to provide a rule of the characterdescribed with a member secured to the end of the rule, and adapted toserve as either a hook or pivot, and a slide arranged on said rule andadapted to serve either as a scribable hook rule marker or scribablecompass point.

These and other advantageous objects, which will later appear, areaccomplished by the simple and practical construction and arrangement ofparts hereinafter described and exhibited in the accompanying drawing,forming parthereof, and in which:

Fig. 1 is a side elevational View of a rule provided with my invention,

Figs. 2 and 3 are transverse, sectional views taken on lines 2 2, 3 3,respectively of Fig. l,

Fig. 4 is an elevational view of a member employed in my invention,

Fig. 5 is a perspective view of the channelled bracket employed in myinvention, and showing the rod fragmentarily,

Fig. 6 is a perspective view of the slide employed in my invention,

Fig. 'Z isa perspective View of the collar, and

Fig. 8 isa fragmentary, partly sectional, view taken on line S-'Sro Fig.1.

In carrying. out `my inventiom utilize theordinary steel rule i which isprovided with unit markings adjacent the upper and lowerlongitudinaledges 2f-3 respectively.`

The face of the rule is `provided with a longitudinal groove 5coextensive with the length thereof, for the reception of a'rod l. isprovided with an upturnedendl which passes through an `aperture 3 in achannelled bracket 9 which. receives the member vil 'and holds the sameagainst the end, edge if'of the rule. other end AIl of the rodpassesthrougna'collar i l2 having a transverse slot i3 to receive theend edge ll of the rule; the end il of the rod is threadedly engaged bya nut l2which draws the parts together.

. The channelled bracket 9 is preferablyv provided with cut-out portionsl5 which define arms i6 adapted to receive the member. il and hold thesame positively againstthe end edge lli of the rule; the cut outportions reveal any foreign matter which might ordinarily disturb theaccuracy of the'device.

A channelled slide i8 is longitudinally movable on the rule, the slidehas arms I8 embracing both faces of the rule and has friction means,such as spring tongues E9 slidably engaging the upper longitudinal edge2 of the rule, tohold the slide at any predetermined .position on thevrule and prevent accidental displacement thereof. The slide is furtherprovided with a depend-A ing stud 2l] preferably made of hard metal, thelower edge ZB of the stud being preferably pointed.

To use the device as a hook rule, the slide I8 is moved to anypredetermined marking on the rule. The edge Il of the member Ilconstitutes the hook for the rule, and the point 2l lo1? the slide studconstitutes the scribable point of the rule for ruling lines. The slideIB is provided with a longitudinal slit 2B through which the lowermarkings of the rule are visible. In using the device, the slide isadjusted on the rule so that the front edge 29 of the slide registerswith the predetermined marking; the accuracy of adjustment is checked bynoting whether the marking 3l of the centrally arranged recessed portion3E! of the slide registers with the center marking The rod# 611'() The.,

of that portion of the rule which is visible through slit 28 of theslide. i

A separate metal point 24 may be removably secured to the stud 20 by anysuitable means,

such as by providing a U-shaped clamp 22 adapted to hold the metal pointagainst the stud. Y The clamp 22 has a stud 22 united thereto, a gib 23being movably arranged on the stud. The stud is longitudinally threadedto receive a screw 23 adapted to bear against the gib 23, forcing thelatter against the slide stud 20 (see Fig. 8) thus securely andremovably holding the clamp on the stud.

'Ihe device may be'used as a compass; for this purpose member I1 isprovided with a cutout portion 25, cut at an angle to receive the end Yedge l of the rule l as shown in Fig. l, so that the tip 26 of themember I1 Will bealigned with the end edge l of the rule and willconstitute the pivot of the compass. A piece of lead may be removablysecured to the slide stud 20 to provide the scribable point of thecompass, by any suitable means, as by an arrangement like that shown forholding the metal point 24 to stud 29. The member l1 may be circular incross section as shown in the drawing, or of any other desirable form. Y

'I'he clamp 22 may be provided with any desired or convenient cam orvother means, instead of the screw and toggle arrangement shown, forsecuring it to the slide stud 20. Y

.The foregoing disclosure `is to be regarded as descriptive andillustrative only, and not as restrictive or limitative of theinvention, of which.

obviously an embodiment may be constructed, Vincluding manymodifications, Without'departing from the spirit and scope of theinvention, set 'forth in the appended claims.

.3.5 Having' thus described my invention, WhatI claim as new and desireto secure by Letters Patent, is: Y 1. A device Vof the characterdescribed, comprising a rule provided With a longitudinal groove,

a rod positioned in said groove, a channelled 5 bracket engaging one endof said rod, a member adapted to be heldin said bracket against an endedge of the` rule, andmeans engaging the other end of said rod andengaging the other end edge of the rule to positively and removablysecure the 1 parts together.

2. In a device of the character described, a rule, a channelled bracketprovided with cut-out portions which dene arms, a member positioned insaid bracket, and means engaging the bracket l and rule for positivelyand removably securing the member against an end edge of the rule.

3. A device of the character described comprising a rule, a bracket, amember positioned in said bracket, said member being provided with acutout bevelled portion to receive one end edge of the rule therebyaligning the tip of the member with the edge of the rule to form apivot, and means engaging the bracket and rule to removably securethe'member against the edge of the rule. 2

Vsaid rod and engagingY said rule for removably Vsecuring said bracketto said rule.

JOHNr KNOBLAUCH.

